Trash incinerator rotary furnace



Nov. 26, 1968 s. MATTEINI 3,412,697

TRASH INCINERATOR ROTARY FURNACE Filed Feb. 2, 1967 //q l q 5 4 8 75,4 ifl 8,4 44 f; 46 4 20 mvewrvk Sum/mo M ATTEINI United States Patent 3,412,697 TRASH INCINERATGR ROTARY FURNACE Silvano Matteini, Via Bellosguardo 2, Florence, Italy Filed Feb. 2, 1967, Ser. No. 613,647 Claims priority, application Italy, Feb. 7, 1966, 2,7 87 66 6 Claims. (Cl. 110-14) ABSTRACT OF THE DISCLOSURE A trash incinerator has a tubular body rotatable about a fixed axis and disposed adjacent a stationary end member having an opening therein. A section of the tubular body remote from the end member is perforated to form a grate and is surrounded by a shell which also forms an ash collecting box therebelow. A burner for igniting the trash extends into the box. In addition the tubular body is provided with internal helical fins which distribute the trash inside the body when the body rotates.

The invention relates to a trash incinerator.

The present invention provides a rotary trash incinerator including a tubular body, for rotating in opposite directions about a substantially horizontal axis, a stationary end member having a loading hopper, an unloading door, and smoke draught means, said tubular body having internal helical projections for distribution of trash therein, an outer shell surrounding a perforated portion of the tubular body remote from the end member and forming a chamber therebelow and a burner extending into said chamber at least to initiate combustion of trash in said incinerator.

The present invention further provides apparatus for trash incineration comprising, a tubular body rotatable about a fired axis, a stationary end member having an opening therein, a section of said tubular body remote from the end member being perforated, a shell assembly enclosing the perforated section and forming a chamber vertically therebelow, combustion ignition means extending into said chamber and means projecting from the internal surface of the tubular body operable by rotation of said tubular body to distribute trash therein.

An embodiment of apparatus for trash incineration in accordance with the present invention will now be described, by way of example with reference to the accompanying diagrammatic drawings in which;

FIGURE 1 shows a partially sectioned side elevation of a trash incinerator;

FIGURE 2 shows an end view taken along the line IIII of FIGURE 1; and

FIGURE 3 shows a sectional view taken along the line IIIIII of FIGURE 1.

FIGURE 1 shows supports 2 mounted on a base 1 each carrying a pair of rollers 3, the rollers 3 rotatably support a tubular body 4 having one end sealed by a conical end wall 5. The tubular body 4 has circumferenital tracks 4A which engage with the rollers 3. A drive chain 6, engages with a circumferential gear formed externally on the tubular body 4 and a geared pinion 7A driven by a motor 7. The motor 7 is arranged to rotate the tubular body 4 in both clockwise and counterclockwise directions and also at two or more speeds.

The section 4B of the tubular body 4 adjacent the wall is perforated to form a grate and is surrounded by a stationary shell 8, the shell 8 has an upper section 8A substantially coaxial to the section 4B, and a lower section 8B having sloping walls which in conjunction with two end walls 8C and 8D form a hopper chamber 1. The tubular body 4 forms a combustion chamber F. The two chambers F and I intercommunicate through the grate formed by 3,412,697 Patented Nov. 26, 1968 "ice the perforations in the section 43. The perforations extend across the width a of section 413. An ash collecting box 9 is mounted below the neck of the hopper chamber I so that ash can be withdrawn from the box through an opening therein or by removing the box itself. A burner 10 extends through the end wall 8C and can be used to commence combustion in the chamber F and also to ensure complete combustion in cases of poorly burning trash. The walls of section 8B have openings 11A therein to provide an air inlet to the chamber I, where the burner flame is developed. A regulatable secondary air inlet is provided by the opening 11B, formed in the upper section 8A of the shell 8.

The chamber F has helical =fins 12 extending therein which fins are rigid with and extend radially inwardly from the inner wall of the tubular body 4 as shown in FIGURE 3. Vanes 13 also extend inwardly from inner wall of the tubular body but are directed in a non-radial direction towards the direction of motion of the inner wall when in operation for trash combustion.

The end of the tubular body 4, remote from the end Wall 5, has a stationary wall 14 adjacent thereto and in which there is an opening 14A. A loading hopper 15 is connected to one half of the opening while a smoke stack 16 extends upwardly from the other half. An upwardly opening door 15A gives access to the loading hopper 15. A lower outwardly opening door 17, hinged at 17A is provided for the discharge of the non-burnt residues. A discharge chute 18 enables the removal of the combustion residues. A short baffle 19 at the top of the opening separates the hopper 15 from the smoke stack 16.

Labyrinth seals 20 and 21, are provided between the tubular body 4 and the stationary wall 14, and the tubular body 4 and the end wall 8D respectivley.

The material to be incinerated is introduced by means of the hopper 15 into the tubular body 4 which is rotated during loading at a relatively high speed in the direction of the arrows f so that the fins 12, distribute the material along the length of the tubular 4 of the combustion chamber F towards the section 48. Dependent on the amount of material of a particular load and whether or not further loading is carried out during the first stage of incineration, relatively slower and variable rotational speeds are used.

To start combustion, the tubular body 4 is rotated slowly in the direction of the arrow and the burner 10 is ignited. Flames pass from the burner through the grate section 4B into the chamber F and from there, in the direction of the arrow f to the smoke stack 16. The flames thus ignite all combustible material along the flame path in the combustion chamber F. v

Dependent on the composition of a particular load of material, the burner 10 may be required to burn continuously to ensure complete combustion of the load, or it may be quenched after initial combustion if the material is of such composition as to sustain combustion itself.

The rate of combustion may be controlled by adjustment of the opening 11B, either to control the supply combustion air, or to adjust the smoke temperature.

The radial dimension of the gap C between the concentric sections 4B and 8A is made small so that most of the gases and flames produced by the burner 10 only pass through the lower zone of the grate section 4B. In addition, screens 22A and 22B are provided to bridge the gap on either side of the grate section 4B between the grate section 4B and the section 8 so as to define the upper limit of the chamber 1. The screens are pivoted on the shell 8 and urged to bear in sliding relationship on the grate section 4B only during rotation of the tubular body 4 in the direction of the arroW h, the screens are made to clear the grate section 4B when the tubular body 4 rotates in the opposite direction.

During the combustion, the material is progressively fed by the helical fins 12 in the direction of the arrow f under the slow rotation of the tubular body 4. The ash which is formed eventually passes through the grate section 4B and the chamber I into the box 9. The flame of the burner and/ or the flames provided from the combustion of the material itself ensure the complete reduction to ash of any incompletely burnt particles in the ash. It should be noted that the air entering the chamber I through the openings 11A is heated by the ash, and also enriches the falling ash with oxygen to provide more uniform combustion of the material, the vanes 13, under the rotation of the tubular body 4, tend to gather material from the bottom of the chamber F, raise it, and allow it to fall in the direction of the arrow f so as to pass through the flame paths in the chamber F. Initially during the combustion process the slow rotation of the tubular body 4, tends to level the material in the interior of the tubular body 4, whereas towards the end of the combustion process the inert material residual tends to pile up towards the conical end wall 5. When the combustion has been completed the burnt residue is unloaded by reversing the direction of rotation of the tubular body 4, i.e. in a direction opposite that shown by the arrows f The fins 12 now move the residual material in the direction of the arrow i so that it can discharge itself through the door 17, which is opened for this purpose.

The cycle can now be repeated with a further load of material.

I claim:

1. In a rotary trash incinerator the combination comprising a longitudinally extending tubular body forming a combustion chamber and having its central axis disposed substantially horizotal, said tubular body arranged to be rotate-d in opposite directions about its centnal axis, an end wall secured to one end of said tubular body and being rotatable therewith, a longitudinally extending section of said tubular body located adjacent to said end wall and spaced from the other end of said tubular body being perforated about the circumference thereof and forming a grate-like surface within the interior of the combustion chamber, a stationary end member disposed in the other end of said tubular body, a loading hopper disposed within said end member for supplying material to be incinerated into said combustion chamber, an unloading door in said end member for removing non-burnt residue from said combustion chamber, :a smoke draft means secured to said end member and communicating with said combustion chamber for removing smoke therefrom, a plurality of longitudinally extending helical material distributing projections secured to the inner surface of said tubular body and extending inwardly therefrom, a plurality of axially extending projections secured to the inner surface of said tubular body and extending inwardly therefrom into the combustion chamber, said projections disposed obliquely to the surface of said tubular body, a stationary shell spaced outwardly from and at least partially enclosing said perforated section of said tubular body, walls depending downwardly from said shell below said tubular body and forming a collecting chamber for receiving ash passing through said perfonated section from the combustion chamber,

2. In a rotary trash incinerator as set forth in claim 1, wherein said stationary shell and the opposite surface of said tubular body form a narrow channel therebetween communicating with said collecting chamber, a pair of screen members disposed between said shell and said tubular body positioned on opposite sides of said combustion chamber, and means for urging said screen members against the outer surface of said tubular member to provide a seal across the channel.

3. In a rotary trash incinerator as set forth in claim 1, wherein drive means are disposed in contact with said tubular body for rotating said tubular body, said drive means being operable at different speeds and in opposite directions for high speed operation during the loading of materials into the incinerator, for low speed operation during combustion within the combustion chamber, and for high reverse speed operation after the completion of combustion for transporting non-burnt residue within said combustion chamber to said unloading door in said end member.

4. In apparatus for trash incineration the combination comprising a longitudinally extending tubular body, means for mounting said tubular body for rotation in opposite directions about the central axis thereof, an end wall secured to one end of said tubular body and being rotatable therewith, a longitudinally extending section of said tubular body located adjacent said end wall and spaced from the other end of said tubular body being perforated about the circumference thereof and forming a grate-like surface within the interior of the combustion chamber, wall means enclosing said perforated section of said tubular body and forming a collecting chamber in communication with the interior of said combustion chamber through the perforations in said tubular body, combustion ignition means disposed Within said collecting chamber, mtaterial advancing means comprising a plurality of longitudinally extending helical projections secured to the inner surface of said tubular body and directed radially inward therefrom, a plurality of inwardly directed projections secured to and disposed obliquely to the internal surface of said tubular body for raising and dropping material through the combustion chamber, a stationary end member afiixed to the other end of said tubular body and having an opening therethrough, a loading hopper, an unloading door and a smoke outlet member each in communication with the opening in said stationary end member.

5. In apparatus for trash incineration as set forth in claim 4, wherein a portion of said walls enclosing said perforated section of said tubular body and the opposite surface of said tubular body form a passageway about the exterior of the tubular body communicating at the opposite ends thereof with the collecting chamber formed by said walls, movable flap members disposed in the passageway between said walls and said tubular body at positions spaced on opposite sides of said tubular body, and means for unging said flap members into a closed position across the passage between said walls and said tubular body.

6. An apparatus for trash incineration as set forth in claim 4 wherein said walls forming said collecting chamber lare provided with openings for admitting air into the collecting chamber wherein it is heated by said combustion ignition means for passage into said combustion chamber through the perforation in said tubular body.

References Cited UNITED STATES PATENTS 2,127,328 8/1938 Egan -14 2,238,161 4/1941 Drew et al. 110-14 2,963,996 12/1960 Uhl et al 110-14 3,306,237 2/1967 Ransom 110-14 JAMES W. WESTHAVER, Primary Examiner. 

